This invention relates generally to RFID transponder systems and more particularly for disabling devices and methods of use for selectively disabling RFID transponders when desired.
In response to the inability of conventional toll collection means to meet the demands created by increased highway traffic, automated toll facilities that provide improved toll collection methods and systems have been proposed and are being implemented. These electronic toll collection systems eliminate the manual transactions of conventional toll collection means through the use of radio transmitters and receivers that perform the necessary transactions as a vehicle travels through the automated toll booth. For example, U.S. Pat. No. 7,224,291 (Hassett), which is assigned to the same assignee as this invention, discloses a system for automatic collection of tolls includes an in-vehicle toll processor (e.g., an RFID transponder or tag) having memory for storing a toll-money-available quantity purchased by the user, and a toll-facility-identification site that transmits a toll-facility-identifier signal indicating the identity of the upcoming toll facility. As the vehicle approaches the identification site, the in-vehicle processor receives the identifier signal and calculates the toll to be debited. When the vehicle passes through the toll facility, the in-vehicle processor transmits its identity, its net balance and the toll, which it debits from an account balance. The in-vehicle processor may increment a low balance, in which case it transmits information which is relayed to a central system for billing. Various means for shutting down delinquent in-vehicle components or identifying offender vehicles are described.
In some electronic toll collection applications, it is desirable to disable or temporarily degrade the performance of an RFID tag so that it cannot be read by an interrogating reader. One such situation can occur when more than one RFID tag is mounted in a vehicle windshield, and it is desired to read or write to one tag while preventing any interference from the other. This can occur during RFID system testing, or on actual vehicles that travel interstate highways and are forced to use different tags for various toll roads along the way. Another application is a toll road with high occupancy toll (HOT/HOV) lanes. There may be times where it would be desirable to temporarily disable an RFID tag, such as a windshield sticker tag, such that no toll is paid when traveling through a toll plaza. A person driving in the HOT/HOV lane that had someone else or others in the vehicle with them would be allowed by the toll authority to travel on the toll road without paying tolls. If a person was alone and wanted to drive in the HOT/HOV lane, they too would be allowed, but would have to pay tolls, and therefore would not be allowed to use the tag disabling device.
In the past, RFID tags that were mounted to windshields using hook and loop, or suction cups, or other releasably securable means that allowed easy removal and re-installation of the tags, were disabled by removing them from the windshield and placing them in a metallized bag, pouch or box. For example, the State of New Jersey makes use of “EZPass” RFID tags for its electronic toll collection system. As part of that system the State provides a “silver” (e.g., metallized) “read prevention bag” for users of the EZPass tag. Such users are instructed to insert the tag into the bag for situations where the tag is not to be read at a particular toll plaza. The placement of the tag within that bag will prevent the RFID tag from being read or written to by an interrogating system by shielding the tag from RF energy that the interrogator transmits. In particular, the bag or pouch reflects most or all of this energy, thereby cutting off communication between the tag and the reader. The disadvantage of this type of tag disabling method is that the tag has to be removed from the windshield to accomplish it.
The prior art includes other instances where an RFID transponder can be temporarily shielded so that it cannot be read. For example, Emvelope, Inc. offers a device under the trademark Emvelope® that provides an insert for a wallet or billfold to form a Faraday cage to contain the wireless signals being emitted by RFID chips on cards in the wallet or billfold. Emvelope, Inc. also offers a similar device in the form of a cover for use with passports. Magellan's International also offers a product, which it calls an RFID Passport Wallet, that is arranged to hold and protect passports and credit cards by providing protective shield, so the RF data in the card/passport can only be accessed when the user opens his/her wallet at approved locations.
While the foregoing techniques for temporarily disabling or shielding RFID transponders are generally suitable for their intended purposes for their specific applications, such techniques are not suitable for temporarily disabling RFID transponders that are permanently affixed to a vehicle, e.g., sticker tags bearing RFID transponders secured to the inner surface of the vehicle's windshield or RFID transponders encapsulated in the windshield itself.
Recently, RFID ‘sticker’ tags have become increasingly popular, e.g., Transcore, Inc. provides such tags. These types of tags are less expensive, easier to use, easier to distribute and have more capability than the previous tags constructed of conventional printed circuit boards and housed in a plastic case. Another advantage is that the ‘sticker’ tags are designed to be permanently mounted and thus provide more security from fraud by preventing tags to be moved from one vehicle to another. The disadvantage of not being able to move tags between vehicles is offset by the lower cost so that an individual tag can be issued to each vehicle economically. A disadvantage of the permanently mounted ‘sticker’ tags, however, is that they can't be temporarily disabled. For example, once removed from the windshield, the adhesive on a windshield sticker tag, such as that produced by Transcore, Inc., can be damaged. Since the antenna design in this tag relies on uniform close proximity to the glass for proper operation, the tag cannot be reused. Thus, sticker tags and any other permanently mounted transponder would be read every time it passed within the RF field of an applicable interrogation system, even when the user did not desire to have the RFID tag read, e.g., to disable the tag when it was desired to pay using cash or other means.
RFID tags can be permanently disabled by mechanical destruction of the conductive patterns on the tag. An example is provided in U.S. Pat. No. 7,277,016 (Moskowitz et al.). While permanent tag disabling has certain viable applications, by definition it is unsuitable for applications where the tag is to be disabled only temporarily and so that it can be reused at some later time.
Accordingly a need exists for a device and method to temporarily disable sticker or other permanently mounted tags with the ease and simplicity as has characterized the temporary disablement of hard cased tags (e.g., by removal and placement in a remote location or in a shielding pouch so that the tag could not be read). A need also exists for a device and method for the temporary disablement of a permanently mounted tag to be controlled by the user of the tag without dismounting or damaging the tag. Further still, a need exists for enabling an RFID tag patron to use a permanently mounted RFID transponder, which is more secure than a removable transponder, but still has the flexibility to enable or disable operation of the RFID tag, as necessary.
The subject invention addresses those needs by providing ‘sticker’ tags and other permanently mounted RFID transducers with this same capability of temporary disablement while retaining all the other positive attributes of a permanently mounted tag/transponder. In particular, the subject invention provides a device for application to (e.g., mounting over) the sticker tag or any other RFID transponder fixedly mounted on the windshield or some other portion of the vehicle for the temporarily disabling the RFID transponder, wherein the disabling device is removable, reusable, and able to be stored within a vehicle without being damaged. In addition, the subject invention enables the patron to maintain privacy if so desired.